Golf is a precision club and ball sport in which competing players (or golfers) use many types of clubs to hit balls into a series of holes on a course using the fewest number of strokes. Golf is defined, in the rules of golf, as "playing a ball with a club from the teeing ground into the hole by a stroke or successive strokes in accordance with the Rules."
It is one of the few ball games that does not require a standardized playing area. Instead, the game is played on a golf course, generally consisting of an arranged progression of either 9 or 18 "holes." Each hole on the course must contain a "tee box" to start from, and a "putting green" containing the actual hole. There are various other standardized forms of terrain in between, such as the fairway, rough, and hazards, but each hole on a course, and indeed among virtually all courses, is unique in its specific layout and arrangement.
Golf competition is generally played for the lowest number of strokes by an individual, known simply as stroke play, or the lowest score on the most individual holes during a complete round by an individual or team, known as match play. Stroke play is the most commonly seen format at virtually all levels of play, although variations of match play, such as "skins" games, are also seen in televised events. Other forms of scoring also exist.
Rules and regulations
The underlying principle of the rules is fairness. As stated on the back cover of the official rule book:
Play the ball as it lies, play the course as you find it, and if you cannot do either, do what is fair.
There are strict regulations regarding the amateur status of golfers. Essentially, anybody who has ever received payment or compensation for giving instruction, or played golf for money, is not considered an amateur and may not participate in competitions limited solely to amateurs. However, amateur golfers may receive expenses which comply with strict guidelines and they may accept non-cash prizes within the limits established by the Rules of Amateur Status.
In addition to the officially printed rules, golfers also abide by a set of guidelines called golf etiquette. Etiquette guidelines cover matters such as safety, fairness, pace of play, and a player's obligation to contribute to the care of the course. Though there are no penalties for breach of etiquette rules, players generally follow the rules of golf etiquette in an effort to improve everyone's playing experience.
Penalties
Penalties are incurred in certain situations. They are counted towards a player's score as if there were extra swing(s) at the ball. Strokes are added for rule infractions or for hitting one's ball into an unplayable situation.
A lost ball or a ball hit out of bounds result in a penalty of one stroke and distance (Rule 27–1). A one-stroke penalty is assessed if a player's equipment causes the ball to move or the removal of a loose impediment causes the ball to move (Rule 18–2). If a golfer makes a stroke at the wrong ball (Rule 19–2) or hits a fellow golfer's ball with a putt (Rule 19–5), the player incurs a two-stroke penalty. Most rule infractions lead to stroke penalties but also can lead to disqualification. Disqualification could be from cheating, signing for a lower score, or from rule infractions that lead to improper play.
Equipment
Golf clubs are used to hit the golf ball. Each club is composed of a shaft with a lance (or "grip") on the top end and a club head on the bottom. Long clubs, which have a lower amount of degreed loft, are those meant to propel the ball a comparatively longer distance, and short clubs a higher degree of loft and a comparatively shorter distance. Typically, the actual physical length of each club is longer or shorter, depending on the distance the club is intended to propel the ball.
Golf clubs have traditionally been arranged into three basic types. Woods are large-headed, long-shafted clubs meant to propel the ball a long distance from relatively "open" lies, such as the tee box and fairway. Of particular importance is the driver or "1-wood", which is the lowest lofted wood club, and in modern times has become highly specialized for making extremely long-distance tee shots, up to 300 yards or more in the hands of a professional golfer. Traditionally these clubs had heads made of a hardwood, hence the name, but virtually all modern woods are now made of metal such as titanium, or of composite materials. Irons are shorter-shafted clubs with a metal head primarily consisting of a flat, angled striking face. Traditionally the clubhead was forged from iron; modern iron clubheads are investment-cast from a steel alloy. Irons of varying loft are used for a variety of shots from virtually anywhere on the course, but most often for shorter-distance shots approaching the green, or to get the ball out of tricky lies such as sand traps. The third class is the putter, which evolved from the irons to create a low-lofted, balanced club designed to roll the ball along the green and into the hole. Putters are virtually always used on the green or in the surrounding rough/fringe. A fourth class, called hybrids, evolved as a cross between woods and irons, and are typically seen replacing the low-lofted irons with a club that provides similar distance, but a higher launch angle and a more forgiving nature.
A maximum of 14 clubs is allowed in a player's bag at one time during a stipulated round. The choice of clubs is at the golfer's discretion, although every club must be constructed in accordance with parameters outlined in the rules. (Clubs which meet these parameters are usually called "conforming".) Violation of these rules can result in disqualification.
The exact shot hit at any given time on a golf course, and which club is used to accomplish the shot, are always completely at the discretion of the golfer; in other words, there is no restriction whatsoever on which club a golfer may or may not use at any time for any shot.
Golf balls are spherical, usually white (although other colors are allowed), and minutely pock-marked by dimples that decrease aerodynamic drag by increasing air turbulence around the ball in motion, which delays "boundary layer" separation and reduces the drag-inducing "wake" behind the ball, thereby allowing the ball to fly farther.
A tee is allowed only for the first stroke on each hole, unless the player must hit a provisional tee shot or replay his or her first shot from the tee.
Many golfers wear golf shoes with metal or plastic spikes designed to increase traction, thus allowing for longer and more accurate shots. A golf bag is used to transport golf clubs and the player's other or personal equipment. Golf bags have several pockets designed for carrying equipment and supplies such as tees, balls, and gloves. Golf bags can be carried, pulled on a trolley or harnessed to a motorized golf cart during play. Golf bags have both a hand strap and shoulder strap for carrying, and sometimes have retractable legs that allow the bag to stand upright when at rest.